Introduction: Use of Ketorolac in spinal fusion is limited due to the risk of pseudarthrosis. Recent literature suggested that such an effect could be type- and dose-related. We sought to demonstrate that Ketorolac use was safe with significant opioid-sparing effect and non-inferior fusion rate.

Methods: This is a prospective, double-blinded, randomized placebo-controlled trial designed according to the 2013 SPIRIT Guidelines. It is a two-arm parallel design with a 1:1 randomization. Over a two-year period under 6 surgeons at two sites, consecutive patients who underwent elective 1-3 level minimally invasive thoracolumbar fusion were screened for inclusion/exclusion. Patients with fusion confounders were excluded. A centralized treatment allocation mechanism and Excel-generated block randomization were used. Patients received a 48-hour scheduled treatment of intravenous Ketorolac (15mg IV Q6H) or saline. We implemented a standardized analgesia regimen using a standardized order set. The primary outcome was fusion rate as evaluated XR/CT using the Suk criteria at 6/12 months by a blinded neuroradiologist. The secondary outcomes were morphine-equivalence (MME) in the first 48h postop and during the hospital stay, NSAIDs-specific perioperative complications, VAS, length of stay, and quality-of-life outcomes at 6/12 months. Univariate analysis was used with p <0.05 considered significant. The sample size was estimated to be 600. This is an interim analysis to evaluate the safety and MME reduction.

Results: Sixty-nine patients were analyzed. Patient characteristics and operative data were comparable between the groups except EBL (Tables 1&2). No significant difference in fusion was found at 6-month (Table 3). There was a significant reduction in total/48-hour MME and length of stay for the Ketorolac group (Table 4). The only complication was a superficial hematoma in a ketorolac-assigned patient requiring evacuation.

Conclusions: Ketorolac demonstrated safety, a significant reduction in postoperative opioid use and length of stay when used as part of a multi-modal analgesics regimen after thoracolumbar fusion.

Patient Care: By demonstrating Ketorolac as a safe adjuvant to opioid pain medication in patients undergoing thoracolumbar fusion we can contribute positively to the growing opioid epidemic and offer an additional safe and effective tool when treating postoperative pain.

Learning Objectives: By the conclusion of this session, participants should be able to: 1. Describe the importance of Ketorolac’s safety and effect in reducing opioid use in thoracolumbar fusion, 2. Discuss in small groups Ketorolac’s safety in thoracolumbar fusion, its effect on postoperative opioid use, and length of stay, 3. Identify Ketorolac as a safe adjuvant treatment for postoperative pain following thoracolumbar fusion with opioid-sparing effects and comparable fusion rate.

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